Pliers with pivotally attached cam actuated supplementary jaws



May 29, 1956 EDER 2,747,446

PLIERS WITH PIVOTALLY ATTACHED CAM ACTUATED SUPPLEMENTARY JAWS Filed July 8, 1953 INVENTOR 'saea; M505? ATTO/RNEY' United States Patent Ofice 2,747,446 P' atented May 29, 1956 PLIERS WITH PIVOTALLY ATTACHED CAM ACTUATED SUPPLEMENTARY JAWS George J. Eder, Port Washington, N. Y.

Application July 8, 1953, Serial No. 366,703

Claims. (Cl. 81-47) This invention relates to pliers and more particularly to pliers which are designed to grip an article or element more efficiently than is capable with conventional pliers.

A principal object of the invention is to provide a panof pliers having the usual main gripping jaws in con unction with at least one supplementary jaw which automatically adapts itself to the conformation of the article to be gripped, while applying gripping pressure multilaterally with respect to the article to be gripped.

Another object is to provide a pair of pliers having a pair of conventional gripping jaws, in conjunction with a supplementary jaw which is cam-operated by one of the conventional jaws to provide therewith a gripping contour which is substantially matched to the contour of the work or device to be gripped by the pliers.

A feature of the invention relates to a pair ofpliers having main gripping jaws which approach each other in one general direction upon closure of the pliers, and a supplementary jaw which is linked to one of themain aws in such a way as to move in a direction transverse to the direction of movement of said main jaws.

Another feature relates to an improved pair of pliers having main gripping jaws and supplementary gripping aws pivotally attached to the main jaws to provide an overall gripping surface which substantially conforms to the work or article to be gripped.

Another feature relates to the novel organization, arrangement and relative interconnection of parts which cooperate to provide an improved pair off pliers.

Other features and advantages not specifically enumerated will be apparent after a consideration of the following descriptions and the appended claims.

In the drawing which shows, by way of example, certain preferred embodiments, Y

Fig. l is a plan view of a pair of pliers according to the invention, with the jaws in closed position; v

Fig. 2 is a fragmentary enlarged viewof thepliers of Fig. l in fully opened position;

Fig. 3 is a sectional view of Fig, 1 taken along the line 33 thereof and viewed in the direction of the arrows;

. Fig. 4 is a perspective view of one of the main plier aws;

Fig. 5 is a perspective view of the cam operated supplementary plier jaw;

Figs. 5A and 5B show modifications of the supple.- mentary jaw of Figs. l-S;

Fig. 6 is a plan view of part of a modifiedpair of pliers according to the invention, with the jaws in closed position;

' Fig. 7 isa view of Fig. 6 with the jaws in fully opened position;

Fig. 8 is a sectional view of Fig.: 6 taken along the line 8-8 thereof and viewed in thedirection of the arrows; i

Fig. 9 is a perspective view of one of. the supplementary jaws shown in Figs. 6-8;

Fig. 10. shows a further modification of the invention;

Fig. 11 shows. a still further modification of the invention;

Fig. 12 is; a perspective view of one of the supplementary jaws shown in Fig. 11;

Fig. 13 is a modification of the supplementary gripping jaws of Figs. 11 and 12-;

Figs. 14 and 15 are diagrammatic representations showing non-central slots for receiving the supplementary gripping jaws, so as to enable the gripping to be more easily effected.

Referring to Figs. 1 to 5, the pliers therein shown comprise a pair of main jaws 10, 11 which are pivotally united: to each other by the usual pivot pin 12, the ends 13 and 14 of which are turned over to hold the jaws while permitting their ready opening and closing. The jaws terminate in any well known hand grips 15, 16, by means of which the main jaws 10 and 11 can be opened and closed. In the particular embodiment shown in Figs. l3, the pliers are designed to grip an article which is substantially triangular. in cross section. For that purpose each of the main jaws 10 and 11 is provided with a respective flat gripping face 17, 18, which diverge from each other in opposite directions. The tip of each jaw is. also provided with a flat face 19, 29. The remaining lengths of each of the gripping faces of jaws 10 and 11 are inclined towards each other, thus providing a some what diamond shape opening between the main jaws 10 and 11 when they are in their fully closed position, as shown in Fig. 1.

The jaws 10 and 11 may be identical in construction and one of them is shown in enlarged perspective form in Fig. 4. As will be seen in Fig. 4, each jaw is provided with a recess or slot 21 in the body thereof, these recesses being in. substantial planar alignment to receive the supplementary gripping jaw 22 shown in perspectiv detail in Fig. 5. The top. wall of each slot is designated by the numeral 23, 24, and the bottom wall of each slot is designated by the numeral 25, 26. If desired, these slots may extend completely through each jaw. As shown more clearly in Figs. 1 and 2, the bottom wall 25, 26 of each slot, instead of being straight, is provided with reversely curved portions 27, 28; 29, 30. These surfaces are adapted to engage the bottom edge 31 of the supplementary jaw 22 and act as cams to force the supplementary jaw 22 upwardly in a vertical direction as the main plier jaws are closed. Preferably, the upper edge of the supplementary jaw 22 is somewhat curved but of slightly less curvature than the upper walls 23, 24 of the jaw slots. In order to retain the supplementary jaw 22 with its ends 33, 34 riding in the respective slots 21, 22, the jaw 22 is provided with an inclined opening 35 to receive a fastening pin 36 which passes through the jaw 10. The pin 36 cooperates with the slot or opening 35 to guide the said jaw 22 in its upward and downward movement as the pliers are closed or opened, while permitting the jaw 22 to pivot and accommodate itself during such movement.

Thus, as shown in Fig. 1, when the jaws of the pliers are completely closed the supplementary jaw 22 is positively cammed to its uppermost position automatically as the pliers are closed. This movement is conjointly controlled by the camming surface 27, 29 and by the sliding engagement between the walls of slot 35 and pin 36. In the closed position of the pliers the pin 36 is in engagement with the lower end of slot 35, and the upper edge of jaw 22 is in engagement with or only slightly spaced from the respective upper walls 23, 24 of the aligned jaw slots. In this position the flat central portion 37' on the upper edge of jaw 22 forms with the inclined. faces 17, 18 a substantially triangular gripping opening. As will be seen in Fig. 2, when the pliers are completely opened the jaw 22 is in its lowermost, posistantially diamond shaped or square shaped opening" as the pliers are closed. If desired, this notch may 'be circular (Fig. A) or hexagonal (Fig; 5B), in which cases the cooperating gripping faces of the main jaws are similarly'shaped. I i

From the. foregoing it will be seen that the pliers are provided with three jaws which move'in unison upon l 63. One of the supplementary jaws is shown in perspective view 1 2an d'one edge thereof is provided with a V-shaped cut-out 64 so as to define with the fiat faces 65, 66 of the main jaws -a hexagonal gripping opening.

7 The supplementary jaws 6 2, 63 are supported by the closing and opening of the pliers, the supplementary jaw 22 being cammed upwardly and downwardly 'by' the corresponding cam shaped faces 27, 29 in the bottom walls of the slots 21, 22. The pin 36merely acts as a guide anddoes not carry any substantial part of the thrust. If desired, the corresponding sides of the handles and'16 may be provided with slots 39, 40 which are displaced from each other in a vertical direction when the pliers are fully closed but which are in alignment with each other when the pliers are in open position, as shown in Fig. 2. These slots may be used as gripping slots to strip insulation from an insulated wire,'or the like. If desired, the edges of the slots 39, 40 may be oppositely beveled or sharpened to provide cutting jaws.

Referring to Figs. 6-9, there is shown a modification of the invention wherein, instead of using a single vertical removable supplementary jaw 22, there are provided a pair of separately movable supplementary'jawsj41, 42. Each of the main jaws 10, 11 is provided with a slot 43, 44 having a curved upper wall 45, 46 and a bottom wall having reversely curved camming portions 47, 48, 49, 50.

The supplementary jaws, oneof which is shown in perspective view in, Fig. 9, are identical in construction and each comprises a heel portion 51 of greater thickness than the remainder or toe portion 52 of the jaw. The heel portion 51 is provided with a passageway 51a to receive a pin 54v anchored to the respective main jaw to permit the supplementary jaws to pivot around their respective pins as the pliers are opened and closed; The upper edge of each jaw is provided with a substantially flat median portion 53, and the lower edge 54a of each jaw is curved to cooperate with the corresponding curved portion 47, 49 in the main jaw slots; These latter curved portions 47, 49 therefore act as cams by engaging the curved lower edges 54a of the supplementary jaws 41, 42. It should also be observed that the lower edge 56 of each of. the heel portions 51 of the supplementary jaws is reversely curved to accommodate the curved end 57 of the toe portion of the opposite supplementary jaw.

7 When the pliers are in their fully closed position the supplementary jaws are in the relation shown, in Fig. 6 wherein the curved toe portion 57 of one jaw is in substantial registry with the corresponding curved edge 56 in the heel portion of the opposite jaw. In this relation the fiat edges 53 of each of the supplementary jaws define together with the flat faces 17, 18 of the main jaws a substantially square or four-cornered gripping opening.

The embodiment of Figs. 69 is not necessarily limited to an arrangement of the plier jaws for gripping asquare or rectangular member. For example, as shown in Fig. 10, the main jaws 10, 11 may have circularly curved gripping faces 17a, 18a instead of the flat faces 17, 18 of Fig. 6. Likewise, the pivoted and cammed supplementary jaws 41a and 42a may have their upper edges heavy shouldered walls at the top and bottom of the respective slots 58 59' and the pins 60 and 61 serve merely to hold these supplementary shoulders in place While permitting their relative turning to conform to the contour of the article being gripped. These supplementary jaws have their gripping faces partially extending beyond the edgesof the main jaw faces, as shown by the shaded portions in v Fig. 11. In this embodiment the shoulders in the slots 58, 59 take substantially the entire mechanical thrust when the pliers are tightly closed on the work to be gripped. It will be understood, of course, that the supplementary jaws 62, 63, instead of having a V-shaped cut-out portion may each have a flat face 65, 66 (Fig. 13), or these faces may be cut to any predetermined shape, depending upon the contour of the articles to be gripped. Preferably, although not necessarily, a

cam operated jaw 22 with its associated slot and pin 36, as well as the shoulders 27 and 29 on the plier jaws, are provided as in the embodiment of Figs. l'5, thus completing the desired contour of the gripping opening andapplying gripping force in mutually transverse directions. In all the foregoing embodiments it willbe understood that the inner faces of the main jaws and the cooperating gripping edges of the supplementary jaws may be knurled or grooved in the event that the pliers are designed tovbe used for crimping the surface of the work to be gripped. It will be understood, therefore, that the pliers according to the invention maybe used for crimping, squeezing, screwing and unscrewing nuts, bolts, pipes, rods, for nutcracking purp.oses,.and the like, or in any other application where it' is desired to grip, squeeze, or otherwise apply the plier pressure multilaterally on the work in stead of merely bilaterally, as in the case of conventional pliers or wrenches.

In all of the foregoing embodiments it has been assumed that the slots in the main gripping jaws are lo;

cated centrally thereof. In certain cases, however, it may be desirable to have the supplementary gripping jaws offset with relation to the center plane of the main jaws.

- This is particularly important, for example, where the ,1 to 5), the main jaws have their slots 21, 22 which receive the ends of the supplementary jaw offset laterally to one side of the center line of the jaw as indicated schematically in Fig. 14. Of course, where the pliers are of the type employing a pair of supplementary jaws (Figs. 6-10), this slot 51 is of double the width so as to ac provided with circularly curved median portions 53a, I

the slots in both of the main jaws, as explained above in It will be understood,

commodate both jaws and is likewise offset laterally from the center line of the main jaw, as indicated schematically in Fig. 15.

Various changes and modifications may be made in the disclosed embodiments without departing from the 'spirit and scope of the invention.

What is claimed is: 1. A plier tool comprising a pair of main gripping jaws pivotally united for gripping motion in a direction 1 towards each other, a pair of supplementary gripping jaws,

each having-a gripping edge defining with said main jaws a gripping opening of predetermined contour, said supplementary jaws extending substantially transverse to said main jaws and each pivotally anchored to only a corresponding one of said main jaws, and a curved camming shoulder on each main jaw against which one edge of the corresponding supplementary jaw on the other main jaw abuts for imparting a positive thrust to said supplementary jaws as said main jaws are being closed.

2. A plier tool according to claim 1 in which each of said main jaws has a slot to receive a corresponding supplementary jaw, each slot having a curved bottom wall which forms the camming shoulder for the corresponding supplementary jaw.

3. A plier tool comprising a pair of main gripping jaws each of said jaws having a curved shoulder, and a pair of supplementary jaws each pivotally attached to only a corresponding one of said main jaws with the edge of each supplementary jaw in thrust conveying contact only with a corresponding one of said shoulders on the other main jaw as the said main jaws are being closed.

4. A plier tool according to claim 1 in which each of said main jaws has a slot having a curved lower wall,

6 each of said supplementary jaws being pivotally mounted within a corresponding one of said slots, each supplementary jaw having a curved periphery corresponding to the curvature in the bottom wall of the associated slot, and each supplementary jaw having a gripping face corresponding to the contour of the article to be gripped.

5. A plier tool comprising a pair of main gripping jaws pivotally united for gripping motion towards each other, a first supplemental gripping jaw pivotally attached to only one of said main jaws, a second supplemental gripping jaw pivotally attached to only the other of said main jaws, respective shoulders on each of said main jaws and each engaging only the supplemental jaw on the other main jaw to impart gripping thrust to said supplemental jaws as said main jaws are moved towards each other.

References Cited in the file of this patent UNITED STATES PATENTS 1,449,486 Anton Mar. 27, 1923 1,498,488 Stallings June 17, 1924 1,806,339 Ferris et a1. May 19, 1931 1,920,413 McGary Aug. 1, 1933 

